Multiple-fuse plug



Patented Oct. 14,1919.

INVENTOR ATTO R N EYS FREDERICK A. FELDKAMP, 0F NEWARK, NEW JERSEY.

MULTIPLE-FUSE PLUG.

Specification of Letters Patent;

Patented Oct. 14, 1919.

' Application filed March 31, 1919. Serial No. 286,264.

To all whom it may concern Be it known that I, FREDERICK A. Fun)- KAMI, a citizen of the United States, residing at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Multiple- Fuse Plugs; and I do hereby declare the following to be a full, clear, and exact description of the invention,- such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to characters of reference marked thereon, which form a part of this specification.

- The present invention relates, generally, to improvements in fuse plugs; and the invention has reference, more particularly, to an improved construction of multiple fuse plug.

The present invention has for its principal object to provide a very cheap, simply constructed and easily manipulated multiple fuse plug, having the general exterior construction and appearance of a single fuse plug, so that the same may be inserted in the usual manner in a receiving socket connected in the electric circuit to be served, but which is so constructed that its inner end contact button may be successively electrically engaged, upon the performance of a simple operation, with the plurality of fuse, elements contained within the interior of the fuse. plug body, until all of said fuse elements have. been utilized or consumed.

Another object of the invention is to provide a very cheap, simple eflicient and easily assembled socket-thread engaging contact element, which eliminates, by its use, the necessity of employing the. expensive male thread shells with which fuse plugs are ordinarily provided.

Other objects of the present invention, not at this time more particularly enumerated, will be clearly understood from the following detail 'd description of the same.

\Vith the various objects of the present invention in view, the same consists, primarily, in the novel constructionof multiple fuse plug hereinafter setforth; and, furtherinore, the invention consists in the novel arangements and combinations of the various parts. as well as in the details of the construction thereof. all of which will be hereinafter more fully described and claimed.

The invention is clearly illustrated in the accompanying drawings, in which Figure 1 i a side elevation of my novel construction of multiple fuse plug; Fig. 2 is an inner end elevation of the same; and Fig. 3 is an outer end elevation of the same:

Fig. 4 is a longitudinal transverse section, taken on line H in said Fig. 2, said view being drawn on an enlarged scale; Fig. 5 is a cross-section taken on line 5-5"in said Fig. f; Fig. 6 is a cross-section taken on line 6-6 in said Fig. 4; and Fig. 7 is a cross-section taken on line 7-7 in said Fig. 4.

Fig. 8 is a part side elevation and part longitudinal transverse section taken on line 88 in said Fig. 2 to show the arrangement of the novel socket-thread engaging contact element.

Fig. 9 is a view similar to that shown in Fig. 8, but in which the ordinary male thread shell is substituted for the novel gpcket-tln'ead engaging con-tact element of Fig. 10 is a cross-section, similar to that shown in Fig. 5, but illustrating a modified form of construction and mounting of an anchor ring with which all the fuse elements are connected and in part supported.

Similar characters of reference are employed in all of the liereinabove described views, to indicate corresponding'parts Referring nowto the said drawings, the reference character 1 indicate a:fuse plug body, which is constructed of sonic suitable insulating material, such as fiber,'porcelain, or the like. The outer end of said plug body is provided with an outwardly extending annular shoulder 2. Associated with the inner end of said fuse plug body 1 is a movable member or head 3 which is also constructed of some suitable insulating material.

Said movable member or head 3 is provided with a metallic contact. button centrally disposed and exposed on the outer side of the same. Said contact button l is provided with a shank-portion 5 which extends rearwardly through said movable member or .head 3. Arranged on the rearward side of said movable member or head 3 is a radially ofiset contact arm (3, through which the said shank-portion 5 extends so that its end may be riveted over said contact-arm to both mechanically and electriits free end with cally couple the same with said contactbutton 4. Said cont-act arm 6 is provided at a rearwardly projecting contact member 7, which extends beyond the rear face of said movable member or head 3. The main body of said contact arm 6'is preferably countersunk in the rear face of .said

movable member orhead 3, so thatthe same with al'ayer of-suitable inmay be covered I sulating material 8 through which the coir tact member 7 pro]ects,.so that the latter is alone exposed to thei'exiientf' of{ijcs pr ojection from the plane of said-rear faceof said movable member or head 3.' Said contact. button 4 with its shank-portion 5 is proyided with a longitudinally extending opening 9,

passing therethrough,'an having a slightly enlarged annular seat 10 at its outer end. Extending through this opening 9 is a stem or rod 11, provided zat its outer end with a slightly enlarged head-member12 which is countersunk in said seat 10, whereby said movable member or heal 3 is maintained in secured relation to the outer end of stem or rod 11, and held against removal therefrom.

Said fuse plug body 1 is provided with a central longitudinally disposed slideway 12 extending therethrough-from its inner end, and terminating toward its outer end in a diametrically enlarged opening 13.

The free end of said stem or rod 11 extends through and is slidably disposed in said slideway 12 so as to enter said enlarged opening as to-coil about said stem or rod 11 is a compression spring 1 1. The free end of said stem'or rod 11 is provided with screwthreads to permit the engagement therewith of a nut-member 15, against which the outer end of said spring 14 bears, so as to exert an inward thrust upon said stem or rod 11 to draw up and maintain said movable member or head 3, in normal closed relation against the inner end of the plug body 1.

The said plug body 1 is bored from its outer end to provide a plurality of longitudinally extending fuse chambers or compartments 16, the same being disposed parallel; to and arranged about the longitudinal axis of the plug body. Said fuse' chambers or compartments 16 are open at the outer end of the plug body, at their inner ends by means of traverse partition members 17, preferably forming an integral part of the plug-body. Formed in the inner end of said plug body 1, so as to be respectively alined with the respective fuse chambers or compartments 16, are a plurality of depressed seats or sockets 18, the inner ends of which terminate at the partition members 17 Countersunk in said depressed seats or sockets 18 are fuse anchoring devices, comprising the bottom of said depressed seats or sockets 13. Seated in said opening 13, so

but are closed heads19 disposed in 18, and shank portions 20 which pass through said partition members 17 so as to enter said fuse chambers or compartments 16. Said shank portion 20 may be tl'nreaded to screw through said partition members, or they may be otherwise secured to said partition members, as may be deemed most convenient. Secured to the fuse chamber or compartment penetrating ends of said shank portions 20 are fuse elements or wires 21, which respectively extend forwardly through the interior or su dive fuse chambers or compartments in alinement with the longitudinal axes thereof.

Gountersunk in the face of the outer end of said plug body 1 is an anchor ring 22 provided in connection with its inner periphcry with inwardly turned anchor tongues or lugs 23, which respectively enter the outer ends of said respective fuse chambers or compartments 16, and to which are secured by means of solder 24 or other desired means, the opposite ends of said fuse elements or wires 21, so that each fuse element or wire is both mechanically and electrically connected with said anchor ring.

Said plug body 1 is provided, in its outer cylindrical surface, with a longitudinally extending channel or groove 25 in which is fixed a socket-thread engaging contact element 26, which is provided with a series of outwardly projecting longitudinally disposed serrations 27 adapted to conform to the thread channels of the screw-threaded female contact shell with which the receiving socket in which the fuse plug is to be screwed is provided. Said contact element 26 has a tail piece 28 which passes through an opening 29, provided therefor in the plug bod into en a 'ement with said anchor ring 22, the body of which it penetrates, and

j with said anchor ring 22.

Each fuse chamber or compartment 16 is adapted to be filled with a desirable filler powder, or other similar material, such is commonly used in fuse devices, and which is adapted to absorb the vapors generated by the burning of the fuse element or wire, although in order not to interfere with the clear illustration of the mechanical structure of my invention, graphic illustration: of such filler has been omitted from the drawings. The disposition of the fuse elements or wires in each compartment or chamber 16 is such that the filler powder will entirely surround and envelop the same as well as the anchor tongues or lugs 23 of the anchor ring 22. After the chambers or compartments 16 are filled with the filler powder, the open ends thereof are closed over by an insulator disk 31, which also eX tends over the outer surface of the anchor ring 22. A cap 32 is then placed over the outer end of the plug body 1 to hold said disk 31, the marginal edges 33 of said cap being turned over and around the annular shoulder 2, to hold the cap in secured ttSSGilb bled relation to the plug body 1.

Normally the movable member or head is drawn back and maintained against the inner end of the plug'body 1, in which position it so disposes the contact member 7 that the same enters a seat or socket 18, so that its free end electrically engages a head 19 of shank-portion 5 the fuse anchoring device located therein. lVhen thus arranged the fuse plug is ready for use, and may be screwed into a receiving socket connected in the electrical circuit to be served thereby. When screwed into such receiving socket, the contact element 26 electrically engages the threaded contact shell of such receiving socket, while the contact button 4. electrically engages the central contact element of. such receiving socket. The fuse plug is thus electrically connected in the circuit to be served thereby, so that the current flows into said con tact button 1 and is conducted through the and contact arm 6 to the contact element 7. The contact element! engaging a head 19 of a fuse anchoring device passes the current into the fuse wire orelement (JODDQCtGdI WltlI the engaged fusev anchoring device. The current passes through the fuse wire or element into the anchor-ring 22, and thence through the contact element 26 to the contact shell of the receiving socket, thus completing the circuit through one of thefuse'wires or elements of the fuse plug, while the remaining fuse wires or elements are cut out of such circuit.

When the particular fuse wire or element thus connected in circuit is burned out or blown, the fuse plug is unscrewed from the receiving socket, and the movable member or'head 3 is moved longitudinally outward against the tension of the spring 14, which movement withdraws the contact member 7 from engagement with the blown fuse anchoring device, and retracts the same from the seat or socket 18, as illustrated by the dotted lines in Fig. 4: of the drraWings. Now the said movablemember'or head 3 may be given a partial rotation on the stem or rod 11, to locate said contact member opposite the next adjoining seat or socket 18,

and then released to permit the spring 14: to draw in the stem or rod 11, and thus return the movable element or head 3 to normal position against the end of the plug body 1. As said movable element or head thus moves back to said normal position, the contact element 7 enters said last mentioned seat or socket 18 to electrically engage the fuse anchoring device located therein, thus electrically connecting a new fuse element or wire between thecoutact member 7 and the element or wire,

contact, clement 2'6, so that the fuse plug may be again screwed into the receiving socket to electrically insert the new fuse elev ment or wire in the circuit to be served.

lhese'0perations may be repeated until all the fuse wlres have been ut lized and blown.

One of the advantages which my novel construction of multiple fuse plug provides, lies in the fact, that when the same is screwed into the receiving socket, to connect the same in circuit, not only is the movable member or head 3 forced, by the threaded engagement of the fuse plug with the receiv ing socket, to maintain a good firm engage structed by the receiving socket from any accidental outward movement: Furthermore, when screwed into place the movable member or head '3 is concealed within the receiving socket, and cannot be tampered with so that the fuse plug cannot be manipulated or otherwise disturbed while it is screwed home into the receiving socket, and consequently idle or mischievous tampering with the fuse plug mechanism cannot be accomplished, without entirelyremoving the fuse plug.

The fuse plug body 1 may be provided on its exterior surface, adjacent to said movable member or head 3, with suitable indieating marks 3st denoting the position of the respective fuse chambers and their fuse elements, and in like manner the exterior surface of said movable member or head 3 may be provided with asuitable indicating mark 35 denoting the position of said contact member 7, so that by selectively regis-' tering the mark 35 with one of the marks 34, the contact member 7 may be brought into electrical contact with a desired fuse element or wire, to set the fuse plug ready for operation. i7

While I have illustratedin the drawings a I fuse plug body 1 possessing four compartments, each containing its individual fuse it will be clearly understood that the number of such compartments and fuse elements or wires may be decreased or increased within practical limits.

Referring now to Fig. 9 of the drawings, I have illustrated therein the novel construction of fuse plug body provided with an ordinary male screw threaded contact shell 36, in place of'the contact element 26 above described. Said shell 36 is provided with a tongue 37 which is passed through an opening inthe body 1, so as t iengage said anchor ring to electrically connect said shell 36 with said ring Referring to Fig. 10 of the drawings, 1 have hown a slightly modified construction and arrangement of anchor ring device. Instcad of using the flat anchor ring 22 having thc anchor tongues or lugs '33, I provide a flat strip bent edgewise into ring shape, and then countersunk edgewise in the outer end of said plug body 1. so as to intersect (w ll fuse compartment 16, thus providing an anchor ring 38. Each portion of the anchor ring 38, which cross the ends of the compartmcnts 16 is indented as at 39 to provide a scat for the end of the fuse elements or wires which, as thus positioned, are sol dered in connected relation to the anchor ring. The said indentaticms are so positioned as to alinc themselves with the axes of the compartments 16 so as to maintain the fuse elements or \vii cs cent-rally located therein. Th tail piece '28 of the contact element '20 is notched in its end to straddle said anchor ring 38, so that the same may be both electrically and mechanically connected therewith. Aside from the above stated modifications, the novel fuse plug is constructed in the same way, and Operates in the same manner as already above described.

I claim l. A multiple fuse plug comprising a plug body. a head connected with the inner end of said plug body so as to be capable of movement relative to said plug body, a pinrality of fuse elements withinsaid plug body. an exterior contact element on said plug body, a common means for electrically connecting said fuse elements with said exterior contact element, an exterior contact button carried by said movable head,,and mean controlled by the movement of said head for electrically connecting any one of said fuse elements with said contact button.

2. A multiple fuse plug comprising a plug body having a plurality of compartments, a head connected with the inner end of said plug body so as to be capable of movement relative to said plug body, a fuse element in each compartment, an exterior contact element on said plug body, a common means for connecting the outer ends of said fuse elements wit-h said exterior contact element, a fuse element anchoring device connected with the inner end of each fuse element, an exterior contact button carried by said movable hcad, and means controlled by the movement of said ncad for electrically engaging a fuse element anchoring device for electrically connecting any one of said fuse elefor electrically connecting each fuse element with said exterior cont act element. a contact button on said movable head. a con tact member on the inner side, of said head electrically connected with said contact button, and individual fuse anchoring devices respectively connected with the inner end of each fuse element with which said contact member. may be selectively engaged by movement of said headt. A multiple fuse plug comprising a plug body, an axially alined stem arranged with said body for longitudinal slidable movement relative thereto and adapted to project from the inner end of said body, a head mounted on the exterior end of said stem, spring means associated with said stem for retracting the same to hold said head normallyagainst the inner end of said body, a plurality of fuse elements within said plug body, an exterior contact element on said plug body, a common means for electrically connecting said fuse elements with said exterior contact elen'ient, an exterior contact button carried by said head, and means controlled by the moven'ient of said head for electrically connecting any one of said fuse elements with said contact button.

A multiple fuse plug comprising a plug body having a plurality. of longitudinal compartments parallel to the axis of said body, an axially alined stem arranged with said body for longitudinal slidable movement relative thereto and adapted to project from the inner end of said body, a rotatable head mounted on the exterior end of said stem, spring means associated with said stem for retracting the same to hold said head normally against the inner end of said loody, an exterior contact element on said body, a fuse element in each compartment, a common means at the outer end of said body for electrically connecting each fuse element with said exterior contact element, an individual fuse element anchoring device connected with the inner end of each fuse element, an exterior contact button carried by said head, and a contact member on the inner side of said head electrically connected with said contact button, said contact member being adapted by manipulation of said head to be selectively engaged with said individual fuse anchoring devices for electrically connecting a desired fuse ele-. ment between said contact button and said exterior contact element.

6. A multiple fuse plug comprising a plug body having a plurality of longitudinal compartments parallel to the axis of said body, a movable head connected with the inner end of said plug body so as to be capable of both longitudinal outward movement and rotary movement relative thereto, a fuse element in each compartment, an anchor ring connected with the outer end of into electrical engagement with said plug body to which the outer ends of said fuse elements are connected, a contact element embedded in the outer surface of said plug body provided with a plurality of longitudinally alined outwardly projecting serrations adapted to engage the threaded contact shell of a receiving socket, said con tact element having a tail-piece extending said anchor ring and secured thereto, a contact receiving means at the inner end of each compartment to which the inner ends of said fuse elements are respectively secured, a central exterior contact button on the outer of said movable head, and a contact member on the inner side of said head, electrically connected with said contact'button, said contact member being adapted by manipulation of said head to be selectively engaged with said contact receiving means for electrically connecting a desired fuse element between said contact button and said contact element.

7 A multiple fuse plug comprising a plug body having a plurality of longitudinal compartments parallel to the axis of said body, a movable head connected with the inner end of said plug body so as to be capable of both longitudinal outward movement and rotary movement relative thereto, a fuse element in each compartment, an anchor ring connected with the outer end of said plug body to which the outer ends of said fuse elements are connected, a contact element embedded in the outer surface of said plug body provided with a plurality of longitudinally aline'd outwardly projecting serrations adapted to engage the threaded contact shell of a receiving socket, said contact element having a tail-piece extending into electrical engagement with said anchor ring and secured thereto, a contact receiving means at the inner end of each compartment to which the inner ends of said fuse elements are respectively secured, a central exterior contact button on the outer face of said movable head, a contact member on the inner side of said head, electrically con-- nected with said contact button, said contact member being adapted by manipulation of said head to be selectively engaged with said contact receiving means for electrically connecting a desired fuse element between said contact button and said contact element, said lug body having an annular laterally proecting shoulder at its outer end, an insulator plate closing the outer ends of said comartment-s, and a cap extending over said lnsulator plate and engaged over said shoulder to secure said insulator plate in place.

8. A multiple fuse plug comprising a plug body having a plurality of longitudinal compartments parallel to the axis of said body, said compartments being closed at their in ner ends and open at their outer ends, an axially alined stem arranged within said face body for longitudinal slidable movement relative thereto and adapted to project from the inner end of said body,'a rotatable head mounted on the exterior end of said stem, spring means associated with said stem for retracting thev same to hold said head normally against the inner end of said body, a fuse element in each compartment, an anchor ring connected with the outer end of said plug body to which the outer ends of said fuse elements are connected an exterior con'tact element go'nsaidplug body electrically connected with said anchor ring, a contact receiving means entering the inner closed end of each compartment to which the inner ends of said fuse elements are respectively connected, a central exterior cohtact button on the outer face of said head, a cont-act member on the inner side of said head electrically connected with said contact button, said contact member being adapted by manipulation of said head to be selectively engaged with said contact receiving means for electrically connecting a desired fuse element between said contact button and said exterior contact element, an insulator plate arranged over the outer end of said plug body to close the outer ends of said compartments, and a cap extending over said insulating plate and secured to said plug body.

9. A multiple fuse plug comprising a plug body having a plurality of longitudinal compartments parallel to the axis of said body, said compartments being closed at their inner ends and open at their outer ends, an axially alined stem arranged within said body for longitndin l slidable movement relative thereto and adapted to project from the inner end of said body, a rotatable head mounted on the exterior end of said stem, spring means associated with said stem for retracting the same to hold said head normally against the inner end of said body, a fuse element in each compartment, an anchor ring connected with the outer end of said plug body to which the outer ends of said fuse elements are connected, a contact element embedded in the outer surface of said plug body provided with a plurality of longitudinally alined outwardly projecting serrations adapted to engage the threaded contact shell of ,a receiving socket said contact element having a tailpiece extending into electrical engagement with said anchor ring and secured thereto, a contact receiving means entering the inner closed ends of each compartment to which the inner ends of said fuse-elen'ients are respectively connected, a central exterior contact button on the outer face of said head, a contact member on the inner side of said head electrically connected with said contact button, said contact member being adapted by manipulation of said head to be selectively engaged with said contact receiving means for electrically eonncctin; a desired fuse element between said contact button and said exterior contact ele ment, an insulator plate arranged over the outer end of said plug body to close the outer ends of said compartments, and a cap extending over said insulator plate and secured to said plug body.

10. A multiple fuse plug comprising a plug body. a head connected with the inner end of said plug body so as to be capable of n 1ovement relative to the latter. a plurality of fuse elements within said plug body, an exterior contact element embedded in the outer surface of said plug body provided with a plurality of longitudinally alined outwardly projecting serrations adapted to engage the threaded contact shell of a receiving socket, a common means for electrically connecting said fuse elements with said exterior contact element, an exterior contact button carried on the outer face of said head and means controlled by the movement of said head for electrically connecting any one of said fuse elements with said contact button.

11. A multiple fuse plug comprising a plug body, an axially alined stem arranged nuts-L with said body for longitudinal slidablc movement relative thereto and adapted to project from the inner end of said body a rotatable head mounted on the exterior end of said stein, spring meansassociated with said stem for retracting the same to hold said head normally against the inner end of said body, a plurality of fuse elements within said plug body. an exterior contact element embedded in the outer surface of said plug bodyprovided with a. plurality of longitudinally alincd outwardly projecting serrations adapted to engage the threaded contact shell of a receiving socket. a common means for electrically connecting said fuse elements with said exterior contact element, an exterior contac button carried on the outer face of said head, and means controlled by the movement of said head for electrically connecting any one of said fuse elements with said contact button.

In testimony that I claim the invention set forth above I have hereunto set my hand this 27th day of March, 1919.

FREDERICK A. FELDKAMP.

Yi'ituesses:

thione e l). RICHARDS, Barnum SUTTERI N. 

